#include //bzero();

#include //atoi();exit(); #include //close(): #include

#define N 64

typedef struct sockaddr SA;

int main(int argc, char *argv[]) {

if(argc < 3) {

printf(\,argv[0]); exit(-1); }

int listenfd, connfd;

struct sockaddr_in myaddr, peeraddr; char buf[N] = {0}; size_t n;

socklen_t mylen, peerlen; mylen = sizeof(myaddr);

peerlen = sizeof(peeraddr); /* create socket */

if ((listenfd = (socket(PF_INET, SOCK_DGRAM, 0))) < 0) {

perror(\); exit(-1); }

/* bind initialization */ bzero(&myaddr, mylen);

myaddr.sin_family = PF_INET;

myaddr.sin_port = htons(atoi(argv[2])); inet_aton(argv[1], &myaddr.sin_addr);

if(bind(listenfd,(SA *)&myaddr, sizeof(myaddr)) < 0) {

perror(\); exit(-1); }

/* listen */ listen(listenfd, 5); /* accept */

if(-1 == (connfd = accept(listenfd, (SA *)&peeraddr, &peerlen))) {

perror(\); exit(-1); }

printf(\,inet_ntoa(peeraddr.sin_addr), ntohs(peeraddr.sin_port)); /* recv-send */ while(1){

n = recv(connfd, buf, N, 0); buf[n] = 0;

printf(\,n,buf); if(0 == strncmp(buf,\,4)) break;

send(connfd, buf, strlen(buf), 0); }

close(connfd); close(listenfd); exit(0); }

资料博客源地址：

http://www.cnblogs.com/lr-ting/archive/2012/08/24/2652482.html